mercoledì 30 giugno 2021

# gst: weird Nature; randomly arranged nanowire networks seem to behave, at the edge of chaos, like cortical neuronal cultures

<< an artificial network of nanowires can be tuned to respond in a brain-like way when electrically stimulated. >>️

<< If the signal stimulating the network was too low, then the pathways were too predictable and orderly and did not produce complex enough outputs to be useful. If the electrical signal overwhelmed the network, the output was completely chaotic and useless for problem solving. The optimal signal for producing a useful output was at the edge of this chaotic state. >>️

<< Some theories in neuroscience suggest the human mind could operate at this edge of chaos, or what is called the critical state, (..) Some neuroscientists think it is in this state where we achieve maximal brain performance. (..) What's so exciting about this result is that it suggests that these types of nanowire networks can be tuned into regimes with diverse, brain-like collective dynamics, which can be leveraged to optimize information processing. >> Zdenka Kuncic.️

<< In the nanowire network the junctions between the wires allow the system to incorporate memory and operations into a single system. This is unlike standard computers, which separate memory (RAM) and operations (CPUs). >>

<< These junctions act like computer transistors but with the additional property of remembering that signals have traveled that pathway before. As such, they are called 'memristors', >> Joel Hochstetter.
'Edge of chaos' opens pathway to artificial intelligence discoveries. University of Sydney. Jun 29, 2021.


Joel Hochstetter, Ruomin Zhu, et al. Avalanches and edge-of-chaos learning in neuromorphic nanowire networks. Nat Commun 12, 4008. doi: 10.1038/ s41467-021-24260-z. Jun 29, 2021.





lunedì 28 giugno 2021

# gst: synchronous dynamics by uncorrelated noise

<< Synchronization is a widespread phenomenon observed in physical, biological, and social networks, which persists even under the influence of strong noise. Previous research on oscillators subject to common noise has shown that noise can actually facilitate synchronization, as correlations in the dynamics can be inherited from the noise itself. However, in many spatially distributed networks, such as the mammalian circadian system, the noise that different oscillators experience can be effectively uncorrelated. >>️

<< Here, (AA) show that uncorrelated noise can in fact enhance synchronization when the oscillators are coupled. Strikingly, (their) analysis also shows that uncorrelated noise can be more effective than common noise in enhancing synchronization. >>️

Zachary G. Nicolaou, Michael Sebek, et al. Coherent Dynamics Enhanced by Uncorrelated Noise. Phys. Rev. Lett. 125, 094101. Aug 24, 2020  



Also

keyword 'error' | 'fuzzy' | 'noise'  in FonT 




keywords 'errore' | 'errori' in Notes (quasi-stochastic poetry)



keywords 'jelly roll' in Notes (quasi-stochastic poetry)





venerdì 25 giugno 2021

# gst: apropos of transitions, tsunami waves generated by granular collapses.

<< Tsunami waves induced by landslides are a threat to human activities and safety along coastal areas. In this paper, (AA) characterize experimentally the waves generated by the gravity-driven collapse of a dry granular column into water. Three nonlinear wave regimes are identified depending on the Froude number Fr_f based on the ratio of the velocity of the advancing granular front and the velocity of linear gravity waves in shallow water: transient bores for large Fr_f, solitary waves for intermediate values of Fr_f, and nonlinear transition waves at small Fr_f. >>️

Wladimir Sarlin, Cyprien Morize, et al. Nonlinear regimes of tsunami waves generated by a granular collapse.    
Journal of Fluid Mechanics, 919, R6. doi:10.1017/ jfm.2021.400. May 28, 2021. 


James Badham. The Science of tsunamis. University of California. Santa Barbara. Jun 21, 2021. 


Froude number (Fr_f)


Also

keyword 'grain' in FonT


keyword 'grani' in Notes (quasi-stochastic poetry)


keyword 'waves' in FonT


keyword 'onda' in Notes (quasi-stochastic poetry)





lunedì 21 giugno 2021

# gst: apropos of transitions, reversing order-disorder of Janus nano particles confined in two dimensions

<< Janus particles with different patch sizes, confined to two dimensions, generate a series of patterns of interest to the field of nanoscience >>

AA << observe reverse melting, where for some densities the system melts under cooling. For a broad range of hydrophobic patch sizes (..), a reentrant transition from solid to liquid and then to an ordered phase emerges as temperature (T) decreases due to the formation of rhombus chains at low T.  This reentrant phase has pseudo long-range orientational order but short-range translational order, >>

The << work provides guidelines to study the melting and assembly of Janus particles in two dimensions, as well as mechanisms to generate phases with specific symmetry. >>️️
Yihao Liang, Boran Ma, Monica Olvera de la Cruz. Reverse order-disorder transition of Janus particles confined in two dimensions. Phys. Rev. E 103, 062607. Jun 9, 2021.


Also

keyword 'nano' in FonT


keyword 'nano' in Notes 
(quasi-stochastic poetry)





sabato 19 giugno 2021

# evol: Megalopta genalis, the bee that flies in the dark with dorsal landmark navigation

<< People -- who get lost easily in the extraordinary darkness of a tropical forest -- have much to learn from a bee that can find its way home in conditions 10 times dimmer than starlight. >>

AA << reveal that sweat bees (Megalopta genalis), find their way home based on patterns in the canopy overhead using dorsal vision. >>️️

<< For a human observer, the most obvious visual cues in the forest at night are gaps in the canopy when we look straight up because the sky is much brighter than the forest below, (..) We see a quite complex pattern of criss-crossing branches, but the bees'-eye-view is much less complex. They see broad blobs of light that vary in shape and position. We knew that ants could use canopy patterns to navigate as they walk through the forest, and we wondered if maybe bees were doing the same thing. >> Eric Warrant.

Dorsal navigation found in a flying insect. Smithsonian Tropical Research Institute. Jun 17, 2021. 


Sandra Chaib, Marie Dacke, et al. 
Dorsal Landmark Navigation in a Neotropical Nocturnal Bee.  doi: 10.2139/ ssrn.3805162. Mar 15, 2021.



sabato 5 giugno 2021

#life: reliability, deception and lies of a signal (among the Siberian jay Perisoreus infaustus)

<< Deception and lies are surprising aspects of human communication and the use of language in which false information is intentionally communicated to others, allowing an individual to gain an advantage over the recipient of such false information. However, language is actually highly pro-social and cooperative and is mainly used to share reliable information. >>️

<< a number of species are able to deceive their conspecifics, including some species of primates and birds like the Siberian jay (Perisoreus infaustus). Siberian jays live in territorial groups and have an elaborate communication system: A wide range of calls allow them to warn each other of the presence of different predators as well as the behaviour of their fiercest enemy, the hawk. >>

<< Occasionally, however, neighbours intruding into a group's territory use the same calls that would otherwise indicate the presence of a perched hawk for a different purpose. Their aim is to deceive the members of the group about the presence of the predator, thus scaring them away to get access to their food.  >>

<< It is a commonly observed phenomenon in the animal kingdom that warning calls are used to deceive others. Clearly, the recipients of the false information potentially pay a high price if they ignore the warning, >>  Filipe Cunha. 

<< Siberian jays thus have a simple rule to avoid being tricked: They only trust the warning calls from members of their own group, meaning cooperation partners. Familiarity alone is not enough, otherwise the birds would also have trusted the calls of their neighbours, >> Michael Griesser. ️

Daniel Schmidtke. Trust among corvids. University of Konstanz. Jun 1, 2021. 


Filipe C. R. Cunha, Michael Griesser. Who do you trust? Wild birds use social knowledge to avoid being deceived. Science Advances. Vol. 7, no. 22, eaba2862. doi: 10.1126/ sciadv.aba2862. May 28, 2021. 


Also

2068 - chaotic probabilities. 
(quasi-stochastic poetry)


keyword "fake" in FonT